JPH05263732A - Fuel pressure regulating valve - Google Patents

Abstract

PURPOSE:To simplify the shape of a valve holding plate, improve accuracy and attain cost reduction through easy manufacture and the improvement of parts control and assemblage while prolonging the life against wear caused by valve operation, vibration, and the like and preventing a ball from falling. CONSTITUTION:In the holding plate 16 of this fuel pressure regulating valve, a holding hole 16a smaller than ball diameter is bored in the center of a thin metal disk in such a way that a ball integral with the valve is turnable and prevented from falling. The hole 16a is independently formed into completely conical shape, and small holes 16b are disposed at the peripheral part of the hole 16a, independently of the hole 16a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION In an internal combustion engine that uses gasoline as a fuel, especially in a fuel supply device of an electromagnetic injection valve for an automobile, the injection pressure from the electromagnetic injection valve is always constant even in the operating state of the engine, and there is little variation. (EN) Provided is a pressure regulating valve which constitutes a valve portion of a fuel pressure regulating valve for supplying pressure and which can greatly improve the operation and life of the valve.

[0002]

2. Description of the Related Art The fuel pressure regulating valve used in the fuel injection system of the electromagnetic injection valve which is currently adopted for most gasoline vehicles all over the world is predominantly of the Bosch system in Germany, and the patent publication in Japan. The one of Japanese Patent Application Laid-Open No. 49-37049 is the most known and widely adopted. This application also claims a holding plate as in the present invention, and the holding plate has a disk-shaped holding plate with three holes formed in a chain and the central hole is extruded into a cone shape (Mt. Fuji shape). However, unlike the present invention, since there is a chained hole on both sides, the central hole does not form a perfect cone, and the two holes on the chained side on both sides are open, and the ball holding surface is about 30-40% less. Further, at this open portion, there are four intersections with the central hole conical portion, but these intersections are pointed and wear due to deviation of the balls, etc., and also the opposing tip of the intersecting portion. Due to variations in the dimensions of the gaps, there are many problems such as the balls becoming easy to come off when they become large and the assembling difficult when they become small.
The holding plate of Japanese Patent Publication No. 49-37049 has a ball portion of a valve assembly in which a ball and a valve have already been welded in a hole that is larger than the ball diameter on both sides, and is submerged in the hole in the central conical portion to form a regular part. It is to be assembled. However, in reality, the ball diameter is 4 ~
It is a small part with a diameter of 5 mm and a disc outer diameter of about 10 mm for the holding plate, so the assemblability is extremely poor. Also, after assembly, it often comes off due to the handling of parts and the logistics process, which proves to be troublesome for automatic or manual assembly. It was Further, in comparison with the product of the present invention, it was found that there is a defect that the crossing tip of the chain portion is worn early even in the durability test.

[0003]

As described in the section of the prior art, how to easily attach the holding plate to the center of the ball and the valve, and the ball contact of the conical portion of the holding plate due to vibration of the ball or the like. The subject was to reduce the wear of the surface portion and prevent the balls from coming off completely to extend the service life of the pressure regulating valve. In order to prevent early wear due to vibration and turning motion of the ball, the contact area of the conical portion of the holding plate is increased, and at the same time, the holding plate can be easily and easily assembled between the ball and the valve. Another problem-solving issue was to have a structure that prevents the balls from sticking to each other due to expansion of foreign matter, fuel, air, etc.

[0004]

As for the wear of the holding portion of the holding plate for holding the ball, in the holding plate of the publicly known example Japanese Patent Publication No. Sho 49-37049, the crossed point with the hole for penetrating the opened ball is chained on both sides. Since it was found that wear occurred near the pointed portion because the valve contacted in the vicinity when the valve was operated, it was decided to simply eliminate the open portion due to this chain hole and make the conical portion completely circular. To do this, of course, it is necessary to change the method of assembling the holding plate.Before welding the valve and ball, place the valve, then put the holding plate, and finally install the ball to electrically weld the ball and valve back and forth. In addition to the ball holding hole in the conical portion, a hole is made in the periphery and the holding plate is assembled to the holder, and then the fuel, air, or foreign matter mixed in between the holder and the holding plate naturally enters the fuel chamber. A means to communicate with was used.

[0005]

As described above, the tongue portion of the holding plate of the known example Japanese Patent Publication No. 49-37049 has a conical portion of the holding plate formed by the movement of the ball which is operated in conjunction with the valve. Since there is an open part, it is a cone with a complete cone closed so that the full surface ball can come into contact with it, and it has a shape that does not wear from the pointed end as shown in the known example, and the assembly order of the holding plate is also a device for hiring. Thus, the valve, the retaining plate, and the ball are assembled in the same direction in this order, and the ball and the valve are welded and fixed to each other, so that it is possible to have a structure in which the ball is not detached during distribution, handling, and use after assembly. In addition, a hole is provided in the flat part of the holding plate independently of the hole for holding the ball in the center to prevent sticking of the ball to the conical part due to expansion of fuel and air existing after the holding plate is assembled to the holder and to prevent the holder from holding. It is possible to eliminate foreign substances mixed in the interior, automate the early wear of the holding plate and the incorporation of balls, and to realize an extremely smooth turning-free driving action without causing product accidents such as ball dropping. Can be done.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a fuel pressure regulating valve which opens and closes a valve by utilizing the operation of a diaphragm to control and supply fuel to an internal combustion engine at a constant pressure. Fuel devices for automobiles that use gasoline as fuel are roughly classified into a carburetor system and a solenoid valve injection system that injects fuel using a solenoid valve. In recent years, the latter solenoid valve injection method has been increasingly used in terms of output improvement, exhaust gas countermeasures, etc. with the development of electronic control technology. However, in this fuel injection type fuel supply system,
Although various technological advances such as various sensors and computers have been made, a fuel pressure regulating valve that generates fuel pressure, which is the direct energy of fuel injection, and constantly maintains a constant pressure and highly accurate fuel pressure with little variation is required. There is. Moreover, it is required to have a simple structure, low cost, no maintenance and inspection, and long life and durability. There is a Bosch type fuel pressure regulating valve as a typical one used in large numbers in such a fuel pressure regulating valve. The characteristic of this pressure regulating valve lies in the structure of the valve portion that can be freely swung, and in particular, it is a holding plate that is devised so that the valve and the ball are integrally formed by welding and that they are freely swung. However, the characteristic of this holding plate is that it is still insufficient to withstand the severe use of the vehicle such as assemblability and wear of the ball holding portion for a lifetime.

The present invention aims to solve these problems of assemblability and durability. The pressure regulating valves of these conventional products and the products of the present invention will be described below.

FIG. 1 shows a cross section of the pressure regulating valve of the present invention. The main body comprises a cover 1 and a case 2 each having a flange, and a diaphragm 3 is swaged at the flange portion to form an air chamber 5 in which a spring 4 for setting a fuel pressure is present. The air chamber 5 is a conduit 6 It is electrically connected to part of the intake passage of the engine. A fuel chamber 7 is provided on the side of the case 2, and a holder 8, a spring 9, a ball 10, a holding plate 11, a valve 12, a valve seat 13, and a fuel pump and an electromagnetic injection valve, which constitute a valve structure mounted on the diaphragm 3, communicate with each other. And a return pipe 15 for returning the fuel to the tank through the opening of the valve 12. In an electromagnetic injection type fuel system, the amount of fuel required for the engine is determined by the amount injected from the electromagnetic injection valve.Since the stroke and the diameter of the plunger of the solenoid valve are constant, it depends on the opening / closing time of the plunger and the fuel pressure to be injected. The supply amount is determined. The opening / closing time of the plunger is set by a computer, but the fuel pressure is affected by the discharge amount of the fuel pump, the discharge pressure, and the characteristics of the pressure regulating valve. Generally, the fuel pump is designed to have a discharge amount of about 2 to 3 times the maximum consumption required by the engine, and a discharge pressure of 3 to 6 kg / cm ^{2 at the} maximum. If the supplied fuel is introduced directly into the electromagnetic injection valve, it is difficult to properly inject and supply the fuel to the engine.Therefore, in general, a fuel pressure regulating valve that keeps the fuel injection pressure constant connects the electric pump and the electromagnetic injection valve. It is used in the rear flow path. This fuel pressure regulating valve returns the fuel amount, which is the difference between the amount of fuel discharged and supplied from the electric fuel pump and the amount of fuel consumed and supplied to the engine, to the original fuel tank and returns the injection pressure of the fuel injected from the electromagnetic injection valve. This is to maintain constant control at all times, and it is necessary to make it possible to inject fuel from the electromagnetic injection valve immediately after the valve of the fuel pressure regulating valve is completely closed and restarted when the engine is stopped. The pressure valve is also required to be a leak-free and highly accurate valve. What is important in the pressure regulating valve is to maintain the fuel pressure at a constant pressure with as little variation as possible while controlling the fuel to be appropriately returned to the original fuel tank. If the variation in fuel pressure is large, the amount of fuel supplied from the electromagnetic injection valve to the engine also varies, and this becomes a major fatal factor that deteriorates fuel economy, drivability, and exhaust gas properties. This is the reason why extremely delicate control of the valve is required. For this reason, it is known that a pressure regulating valve used for a fuel injection system for an internal combustion engine, particularly for an automobile, does not provide delicate pressure control with a simple fixed valve structure simply fixed to a diaphragm. Since this type of pressure regulating valve generally uses a large-capacity fuel pump, it is almost always open during engine operation, but the gap between the valve and valve seat lift when the valve is open is several minutes. It is known that the opening and closing behavior of the valve controls the holding of a constant pressure and influences variations due to a slight lift of about 1 mm. For this reason, a valve directly fixed to the diaphragm is directly affected by the inclination of the spring and the behavior and attitude of the diaphragm, and the valve tilts when opening and closing the valve, making proper and delicate control impossible. Therefore, even if the diaphragm moves freely, the valve has a structure in which the valve is always automatically controlled to have a fixed posture with no inclination with respect to the valve seat. According to this structure, the hysteresis when the valve is opened and closed is extremely small, and stable characteristics can be obtained. The most widely known example of this swing-free swing type valve structure is Japanese Patent Publication No. 49-37049, which is produced in large numbers today because of its excellent patent. Although a swing-type valve has been invented and implemented in many inventions, the Japanese Patent Publication No. 49-37049
No. 3 has the simplest structure and good characteristics, and is used in most pressure regulating valves today. On the other hand, the pressure regulating valve is positioned as an important safety component because it is strictly required not to leak fuel because it handles high pressure in addition to the pressure regulation control characteristics.As for the valve structure, the characteristics affect exhaust gas, so strength and durability In terms of performance, it is required to be used for a lifetime. Therefore, although it has an invisible high design specification, it has a simple structure, and therefore there are many competing manufacturers, the market price is severe, and cost reduction is desired.

The present invention relates to a valve structure of Japanese Patent Publication No. Sho 49-37049, which has been widely adopted and manufactured in the past, for simplifying and reducing the cost.

FIG. 2 shows details of the conventional valve section. The valve 12 is welded to and integrated with the ball 10, and a central portion of the holder 8 is provided with a spring 9 for constantly abutting the ball 10 on the holding plate 11 via a holding plate 11 which holds the ball 10 at an intermediate portion thereof. Installed in the conical recess 8a of the holding plate 11
Is crimped on the outer periphery of the holder 8. FIG. 3 is a detailed view of the holding plate 11. A hole 11a for holding a ball smaller than the ball 10 is formed in the center of a disk of a thin metal plate, and the hole 11a is extruded into a conical shape (Mount Fuji shape) from one side and the hole 11a is formed.
Holes larger than the diameter of the ball 10 linked to the flat parts on both sides of
1b is left open. Therefore, the conical apex of the central hole 11a is formed with the tongue pieces 11c facing each other on both sides.
Four pointed portions 11d are formed in a portion where 1a and the holes 11b on both sides are connected to each other, and the ridge gap dimension G is generated at each of the pointed portions 11d. FIG. 4 shows the assembly of the valve assembly and the holding plate 11. The valve 12 and the ball 10 are integrally fixed by welding in advance to form a valve subassembly, and the ball 10 of the valve subassembly is made to dive into the hole 11b of the holding plate 11 and displaced in the plate surface direction to form a central hole. 11a, and the holder 8 is assembled. When the conventional holding plate 11 of this type is used, the receiving surface of the holding plate 11 that receives the ball 10, that is, the tongue portion 11c requires the groin portion G for incorporating the ball 10. Since the number of bearing surfaces is extremely small, the valve is always open when the valve is open, that is, while the engine is operating, and due to vibrations of the engine, changes in the discharge flow of the fuel pump, and the pulse flow of fuel that accompanies the opening and closing of electromagnetic injection, etc. Always diaphragm 3 and valve 1
2 vibrates and the ball 10 hits the tongue portion 11c of the valve 11 to wear. Further, in the case of the holding plate 11, since the balls are biased to the tip portion 11d and come into contact with the tip portion 11d intensively, the tip portion 11d
It was found that the abrasion was remarkably promoted by the vibration and the turning operation of the ball 10 at the d portion. During the life of the engine, during the life of the engine, for example, repairing the engine, forgetting to refuel with fuel consumption, or heat from the area around the piping after the engine was stopped causes the fuel in the piping to boil and generate steam in the piping. Air often infiltrates into the air, and in this case, when the engine is started, the fuel chamber 7 of the pressure regulating valve is filled with air, so that the diaphragm 3 violently operates, and accordingly, the valve 12 and the ball 1
0 vibrates violently, and the tongue portion 11c and the pointed portion 11d, which are the receiving surfaces of the balls 10 of the holding plate 11, are worn very early, and finally the ball 10 comes off the holding plate 11 and the valve 12 does not work and the engine malfunctions. It leads to dangerous situations such as runaway and stopping. On the other hand, in the valve assembly using the conventional holding plate 11, the ball 10 has a diameter of about 3 to 4 mm, and the disc of the holding plate is a small part having a thickness of 0.5 mm and an outer diameter of about 10 mm. It is a difficult task not only to perform automatic assembly but also to assemble manually by making the ball 10 go through the hole 11b of the holding plate 11 and slide the gap 11d into the central hole 11a, which naturally increases the cost of assembly. Become. Further, with the conventional holding plate 11, even after the ball 10 is dipped into the holding plate 11, the ball 10 often comes off during handling or distribution at the manufacturing site, etc., which not only causes troubles in manufacturing but also causes out-of-stock. Will be done. On the other hand, in manufacturing the conventional holding plate 11, the diameter of the central hole 11a and the two holes 11b on both sides are set.
Variations in the distance between the hole diameter and the hole 11a, the conical extruded height dimension of the central hole 10a, etc., and the handling of parts may cause deformation of the tongue portion, which may cause variations in the crevice dimension G, etc. Then, it was found that there are many problems such that the ball 10 becomes impossible to assemble or easily comes off.

An object of the present invention is to remedy the conventional holding plate 11 and solve the above-mentioned assemblability, durability, handleability of parts, and the like in order to prolong the life of the fuel pressure regulating valve and reduce the cost. It is intended to provide a high quality pressure regulating valve.

FIG. 5 shows a retaining plate 16 according to the present invention. The holding plate 16 of the present invention can be made of the same material, thickness, and outer diameter as the holding plate of the conventional product, but the major difference is that a hole 16a smaller than the diameter of the ball 10 is formed in the central portion. It is formed by extruding one side in a conical shape (Mt. Fuji shape). According to the present invention, the conical portion is completely closed at the slanted conical portion as compared with the conventional holding plate 11. Therefore, even in the press-molding production, since the shape is symmetric and the conical portion has a very high dimensional accuracy due to its simple shape, there is no error in handling during distribution of parts, and part management is hardly required. As long as the press die does not wear excessively, stable parts can be supplied, and the closed conical shape has no dimensional deviation.

Next, FIG. 6 shows the assembly of the holding plate 16 and the valve portion according to the present invention.
7, a valve 12 having a small hole 18a capable of supporting the ball 10 in the central portion is supplied and installed, then the holding plate 16 of the present invention is supplied and installed, and finally the ball 10 is installed and installed in the conical portion of the holding plate 16. Since the ball 10 is supplied to the conical concave portion of the holding plate 16, the ball 10 maintains a stable posture without rolling down. Also, since the bottom of the ball 10 is exposed from the hole 16a of the conical portion of the holding plate 16, the ball 10 is inserted into the small hole 12a of the valve 12. The ball 10 and the valve 12 are integrally welded and fixed by the electrode 18 which can be stably installed and descends from above to complete the valve assembly. During the electric welding, the holding plate 16 is installed so that the holding plate 16 is not discharged and the individual parts and the peripheral device are damaged by the discharge, or the welding current is varied in the welded part so that the welding strength is not deteriorated. Then, the employment 19 can be made into an insulator to enable stable welding.

In the holding plate 16, instead of the small holes 11b for penetrating the balls 10 formed on both sides of the conventional holding plate 11, one hole is formed in the flat portion independently of the conical hole 16a of the central ball holding plate. Alternatively, when the valve assembly is assembled to the holder 8 by making about two small holes 16b, the fuel and air enclosed by the holder 8 and the retaining plate 16 expands, so that the ball 10 is formed in the conical portion of the retaining plate 16. The small hole 16b may be caused because a stick or the like may be caused to impair the turning performance.
Is always open to the fuel chamber 7 of the pressure regulating valve. Further, in the small hole 16b, it is conceivable that foreign matter or the like that has entered from the outside of the pressure regulating valve may adhere to the contact surface between the conical portion of the holding plate 16 and the ball, and the foreign matter is easily discharged from the inside of the valve mechanism. You can play a role that doubles as a function.
Thus, in the fuel pressure regulating valve using the holding plate 16 of the present invention, the assembly of the valve portion can be easily automated and the cost can be reduced.
Further, by enlarging the contact surfaces of the holding plate 16 and the balls 10, the abnormal wear of the extreme parts and the wear of the contact parts are more uniform and the service life can be made longer than the conventional product. The distribution of goods and parts management are easy, and high quality parts can be obtained, and the life of the valve part in the market can be extended to provide users with a lifelong pressure regulating valve.

[0015]

In the holding plate of the present invention, the conical hole (Mt. Fuji shape) for holding the central ball is a completely independent conical hole, so that the contact surface for holding the ball is held at the complete circumference. Due to the shape, wear of the holding plate contact portion due to vibration of the valve and swiveling operation is significantly reduced, and the durability of the valve portion can be more than doubled as compared with the conventional one. At the same time, the small holes provided on both sides allow natural discharge of internal fuel, air, and foreign matter, and the accuracy of the holding hole is affected because the position and diameter of this small hole are completely independent of the central holding hole. Do not do that, because the shape is simple, it is possible to manufacture a highly accurate holding plate, and the shape that does not cause dimensional deviation in the middle process of distribution, etc., and also automatically supply the valve, holding plate, and ball for automatic assembly. It is possible to easily reduce the assembly cost and eliminate the detachment of the holding plate.

[Brief description of drawings]

FIG. 1 is a sectional view of a fuel pressure regulating valve.

FIG. 2 is a detailed sectional view of a conventional valve structure.

FIG. 3 is a view showing a conventional holding plate.

FIG. 4 is a view showing an assembly of a conventional holding plate.

FIG. 5 is a diagram showing a holding plate of the present invention.

FIG. 6 is an assembly view of a holding plate of the present invention.

[Explanation of symbols]

1 ... Cover, 2 ... Case, 3 ... Diaphragm, 4 ... Spring, 5 ... Air chamber, 6 ... Conduit, 7 ... Fuel chamber, 8 ... Holder, 9 ... Spring, 10 ... Ball, 11 ... Conventional holding plate, 11a ... ball holding hole, 11b ... ball assembly through hole, 11c ... holding plate tongue portion, 11d ... pointed portion, 12
... valve, 12a ... small hole for fixing balls, 13 ... valve seat, 14 ...
Introducing pipe, 15 ... Returning pipe, 16 ... Holding plate of the present invention, 16a
... ball holding hole, 16b ... small hole, 17 ... hire, 18 ... electrode, 19 ... hire.

Claims (2)

[Claims] 1. A body is divided into an air chamber and a fuel chamber by a diaphragm, and a spring for setting a fuel pressure is set in the air chamber,
In a fuel pressure regulating valve for an internal combustion engine, which has a valve mechanism interlocked by the drive of the diaphragm in the fuel chamber, a valve seat, an introduction pipe for introducing fuel, and a return pipe for returning fuel to the tank when the valve is opened, a spring is attached to a holder fixed to the diaphragm. In a valve structure composed of a holding plate that holds a valve assembly in which a ball and a valve are integrally welded so as to freely swing and rotate, the holding plate is formed into a thin disk shape and a hole smaller than the ball diameter is formed in the center. Further, the fuel pressure regulating valve is characterized in that the center of the hole is extruded in one direction to form a conical shape. 2. The fuel according to claim 1, wherein one or more independent small holes are provided around the central hole of the holding plate so that the holder, the inside of the holding plate and the main body fuel chamber communicate with each other. Regulator valve.